U.S. patent application number 14/332625 was filed with the patent office on 2016-01-21 for control device using image tracking technology for controlling overhead crane system.
The applicant listed for this patent is Institute of Nuclear Energy Research, Atomic Energy Council, Executive Yuan, R.O.C.. Invention is credited to Cheng-Yuan Chang, Chung-Hao Huang, Sung-Chih Ku, Yen-Nung Lai, Lun-Hui Lee.
Application Number | 20160016763 14/332625 |
Document ID | / |
Family ID | 55073953 |
Filed Date | 2016-01-21 |
United States Patent
Application |
20160016763 |
Kind Code |
A1 |
Lee; Lun-Hui ; et
al. |
January 21, 2016 |
Control device using image tracking technology for controlling
overhead crane system
Abstract
A control device using image tracking technology for controlling
overhead crane system is disclosed, in which a plurality of image
capturers are used to monitor a operating space and a position of
the hoisted load, a respective image of two of which are used to
establish a 3D coordinate data, so that an image processor
calculates parameters including a hoisted load position (P), a
swing angle (.theta.) and a cable length (I) by referring to the
images received, and generates a feedback signal to a crane
controller. The crane controller issues a drive signal according to
the feedback signal to drive the overhead crane system.
Inventors: |
Lee; Lun-Hui; (Taoyuan
County, TW) ; Lai; Yen-Nung; (Taoyuan County, TW)
; Huang; Chung-Hao; (Taoyuan County, TW) ; Chang;
Cheng-Yuan; (Taoyuan County, TW) ; Ku; Sung-Chih;
(Taoyuan County, TW) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Institute of Nuclear Energy Research, Atomic Energy Council,
Executive Yuan, R.O.C. |
Taoyuan County |
|
TW |
|
|
Family ID: |
55073953 |
Appl. No.: |
14/332625 |
Filed: |
July 16, 2014 |
Current U.S.
Class: |
212/275 |
Current CPC
Class: |
B66C 13/063 20130101;
B66C 13/46 20130101 |
International
Class: |
B66C 13/06 20060101
B66C013/06; B66C 19/00 20060101 B66C019/00; B66C 13/18 20060101
B66C013/18 |
Claims
1. A control device using image tracking technology for controlling
a overhead crane system, where the overhead crane system comprising
a movable drive unit, a cable connecting the drive unit and a
hoisted load, wherein the control device comprises: a plurality of
image capturers each continuously capturing images of the hoisted
load within a operating space; an image processor receiving images
from the image capturers to constitute a 3D coordinate data, and
determines if load swing occurs according to the 3D coordinate
data, and converts a movement amount of the load swing into a
parameter to generate a feedback signal; and a crane controller,
electrically connected to the image processor and the drive unit,
the crane controller generate a drive signal according to the
feedback signal, which the drive signal is sent to the drive unit
to modify the speed of drive unit.
2. The control device using image tracking technology for
controlling a overhead crane system in claim 1, wherein the
plurality of image capturers are respectively used to capture the
image of the hoisted load on different planes.
3. The control device using image tracking technology for
controlling a overhead crane system in claim 1, wherein the
plurality of image capturers are circumferentially disposed at a
position on a horizontal plane, respectively.
4. The control device using image tracking technology for
controlling a overhead crane system in claim 1, wherein the image
processor calculates parameters including a hoisted load position
(P), a swing angle (.theta.), and a cable (I).
5. The control device using image tracking technology for
controlling a overhead crane system in claim 1, wherein a fixed
reference point is arranged in the operating space, the hoisted
load hung on a distal end of the cable is taken as a first
monitoring point, a front end of the cable is taken as a second
monitoring point, and the image processor calculates the movement
amount and coverts the movement amount into the parameter according
to an associated position relationship of the first and second
monitoring points with respect to the reference point,
respectively.
6. The control device using image tracking technology for
controlling a overhead crane system in claim 1, wherein the drive
unit comprises a sliding rail, an trolley slidably disposed on
sliding rail, and a load end connected to the trolley through the
cable.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to a control device using
image tracking technology for controlling an overhead crane system,
and particularly to such a device employing an image processing
technology to determine if there is a load swing issue, and more
particularly to such a device using a plurality of image capturers
to monitor a hoisted load and a 3D space where the hoisted load is
located and using the image recognition technology to measure a
movement amount of the overhead crane and the hoisted load, so that
the issues such as detection and load swing suppression may be
achieved, so that the safety issue of a worker in overhead crane
operation area.
DESCRIPTION OF THE RELATED ART
[0002] A prior trolley is operated manually or by a computer. For
the manual control mechanism, a user directs the trolley to move
through a control rod or a control button. However, this manner may
not accurately control a position and movement speed of the
trolley. The computer control mechanism drives the trolley to a
predetermined position by setting up a coordination, and determines
the speed of the trolley through a computer. To be more specific,
the computer control mechanism uses a server motor to drive the
trolley to move. In doing this, an operator inputs a movement
coordination through a computer interface, and an encoder generates
a digital encoding to direct the server motor to move the trolley,
so that the trolley may be moved to the predetermined position.
[0003] Although the computer control manner improves the issue of
the overhead movement accuracy, the manual and computer control
manners both have a common issue to be resolved, i.e. a load swing
issue.
[0004] When the trolley moves, an inertial of the load and a
flexibility of the cable may cause the load to deviate the trolley.
As shown in FIG. 4 for the overhead crane system, with the trolley
31 going along x, y, and z axes having a movement amount f.sub.x,
f.sub.y, and f.sub.z, the load 32 will swing to have angle
deviations .theta..sub.x, .theta..sub.y.
[0005] In the case when the hoisted load is a precision equipment
or a dangerous or radioactive material, the load swing has to be
reduced to a minimum, so that operators may be assured with their
safety. Particularly, the radioactive material processing work is
quite a burden in the Nuclear Research Institute, thus the
operation for moving the radioactive material by the trolley has to
be carefully undertaken to suppress the load swing issue.
[0006] At present, the trolley automation control generally employs
a computer encoding to drive the server motor, so that the trolley
may be moved to a desired position for a hand-off task. For
example, FIG. 5 shows TW patent I279389, which discloses a crane
40, comprising a movement control portion 17, an encoder 42, and a
GPS device 43. Further, wireless devices 45, 46 are communicated to
a remote central computer 50, so that the crane 40 is directed by
the central computer 50 with coordination of the encoder 42 and the
movement control portion 17 to move to a designated position.
However, this technology has its demerit as mentioned above, where
the load may have a deviation from the cane owing to the inertial
of the load and the flexibility of the cable, resulting in the load
swing issue.
[0007] In view of the load swing issue, the overhead crane system
is considered as an activation-absent system, and the swing
suppression can be quite important in the course of control.
Particularly for the place having lots of precision equipment or
radioactive material such as in the Nuclear Research Institute, it
may be quite a crucial lesson for how to reduce the swing level to
a minimum in the course of the trolley's movement. However, the
load deviation is hard to be detected and corrected in the prior
art, and there is still no any resolution about detection and load
swing suppression for the field in any previous patents. Therefore,
the prior technology in this field may not satisfy an actual use
for the user.
SUMMARY OF THE INVENTION
[0008] It is, therefore, a main object of the present invention to
provide a trolley technology by which issues such as detection and
load swing suppression may be addressed by using a plurality of
image capturers for monitoring the trolley, a 3D space where the
hoisted load is located, and an image recognition technology for
acquiring a respective movement amount of the trolley and the
hoisted load, so that the safety issue of a operator in a operating
space.
[0009] To achieve the above object, the present invention discloses
a control device using image tracking technology for controlling
overhead crane system, which hangs and conveys a hoisted load, has
a drive unit, and adjusts a moving speed thereof according to a
corrected drive signal, which comprises a plurality of image
capturer, each continuously capturing an image of the hoisted load;
an image processor receives the images from the plurality of image
capturers, respectively to constitute a 3D coordinate data of the
hoisted load and to determine if load swing occurs according to the
3D coordinate data Then, the image processor converts a movement
amount of the hoisted load into a parameter, and generating a
feedback signal; and a crane controller, electrically connected to
the image processor and the overhead crane system, directing the
overhead crane system to move by issuing a drive signal, and
correct the drive signal according to the feedback signal.
[0010] In an embodiment, the plurality of image capturers are
respectively used to capture the image of the hoisted load on
different planes.
[0011] In an embodiment, the plurality of image capturers are
disposed on the overhead crane system.
[0012] In an embodiment, the plurality of image capturers are
circumferentially disposed at a position on a horizontal plane,
respectively.
[0013] In an embodiment, the image processor calculates parameters
including a handoff article position (P), a swing angle (.theta.),
and a cable (I).
[0014] In an embodiment, a fixed reference point is arranged in the
operating space, the hoisted load hung on a distal end of the cable
is taken as a first monitoring point, a front end of the cable is
taken as a second monitoring point, and the image processor
calculates the movement amount and coverts the movement amount into
the parameter according to an associated position relationship of
the first and second monitoring points with respect to the
reference point, respectively.
[0015] In an embodiment, the overhead crane system comprises a
sliding rail, a trolley slidably disposed on sliding rail, and a
load end connected to the trolley through a cable.
BRIEF DESCRIPTIONS OF THE DRAWINGS
[0016] The present invention will be better understood from the
following detailed descriptions of the preferred embodiments
according to the present invention, taken in conjunction with the
accompanying drawings, in which:
[0017] FIG. 1 is a schematic diagram of a basic architecture
according to the present invention;
[0018] FIG. 2 is a schematic diagram of an image taken by a
simulated operation according to the present invention;
[0019] FIG. 3 is a schematic diagram of a circuit of a negative
feedback of a parameter to an operational logic unit according to
the present invention;
[0020] FIG. 4 is a schematic diagram of a overhead crane system;
and
[0021] FIG. 5 is a schematic block diagram of an in-field movement
crane control device according to the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0022] Referring to FIG. 1 to FIG. 3, in which a schematic diagram
of a basic architecture according to the present invention, a
schematic diagram of an image taken by a simulated operation
according to the present invention, and a schematic diagram of a
circuit of a negative feedback of a parameter to an operational
logic unit according to the present invention are shown,
respectively. The present invention is a control device using image
tracking technology for controlling an overhead crane system.
[0023] The overhead crane system 10 hangs and conveys a hoisted
load (not shown). The overhead crane system 10 comprises a movable
drive unit 105, a cable 104 connecting the drive unit 105 and the
hoisted load. The drive unit 105 adjusts a moving speed thereof
according to a drive signal.
[0024] Wherein, the drive unit 105 comprises a sliding rail 101, a
trolley 102 slidably disposed on the sliding rail 101, and a load
end 103 connected to the trolley 102 through the cable 104, wherein
the hoisted load (not shown) is conveyed and driven by the drive
unit 105.
[0025] Furthermore, the overhead crane system 10 comprises a
control device using image tracking technology for controlling the
overhead crane system 10. The control device comprises a plurality
of image capturers 11, an image processor 12, and a crane
controller 13.
[0026] The plurality of image capturers 11 are disposed on the
overhead crane system 10, and circumferentially disposed at a
position on a horizontal plane with respect to the overhead crane
system 10, respectively. Each of the image capturers 11
continuously capture images of the hoisted load within a operating
space.
[0027] The image processor 12 receives the images from the
plurality of image capturers 11, respectively to constitute a 3D
coordinate data of the hoisted load and to determine if load swing
occurs according to the 3D coordinate data , and then converts a
movement amount of the hoisted load into a parameter, and finally
generates a feedback signal to the crane controller 13.
[0028] The crane controller 13 is electrically connected to the
image processor 12 and the overhead crane system 10. The crane
controller 13 has an operational logic unit 131, which directs the
trolley 102 to move by issuing a drive signal.
[0029] When the trolley 102 moves, the inertial of the hoisted load
and flexibility of the cable 104 may cause the load end 103 swings.
The image capturers 11 capture images of the operating space and
the image processor 12 detects the load swing. The image processor
12 sends the feedback signal to the crane controller 13. The crane
controller 13 corrects the drive signal according to the feedback
signal, so that the movement speed of the trolley 102 is adjusted
to suppress the load swing phenomenon.
[0030] When the present invention is operated, at least two image
capturers 11, such as cameras, are used to capture the images of
the hoisted load from different planes, so that a 3D coordinate
data of the operating space may be established.
[0031] The image capturers 11 monitor the position of the hoisted
load in the operating space, and then the image processor 12
calculates parameters including a hoisted load position (P), a
swing angle (.theta.) and a cable length (I).
[0032] As shown in FIG. 2, in the simulated operation of the
present invention, to determine the associated position of the
overhead crane system 10, a fixed reference point 1 is set in the
operating space for comparison reason. And, the hoisted load hung
at the load end 103 of the cable 104 is taken as a first monitoring
point 2, and a front end of the cable 104 as a second monitoring
point 2a.
[0033] When the simulated operation is proceeded, the first
monitoring point 2 vibrates when the trolley 102 moves, and a
movement amount caused by this vibration may be calculated by the
image processor 12, according to an associated position
relationship of the first monitoring point 2 and second monitoring
point 2a with respect to the reference point 1, respectively.
Further, the movement amount may be then converted into the above
mentioned parameters, such as a position (P), and a swing angle
(.theta.), and a cable length (I). The thus obtained parameters
including the position of the hoisted load, the swing angle, and
the cable length may be feedback to the crane controller 13. In the
crane controller 13, the operational logic unit 131 has an
operation for correcting the drive signal according to the
parameters. As shown in FIG. 3, when the load swing phenomenon
occurs, the position, swing angle and cable length parameters will
be used to correct the drive signal issued by the crane controller
13. The drive unit 105, such as a hoisted load server motor, may
reduce the swing amount of the hoisted load to a minimum by
adjusting the movement speed of the trolley 102 according to the
corrected drive signal.
[0034] In the present invention, a plurality of image capturers are
used to monitor a operating space, and the images captured by at
least two such image capturers are used to establish 3D coordinate
data. Further, the image capturers also track the position of the
hoisted load, so that when the hoisted load is moved on the
trolley, the image information is continuously feedback to the
image processor in the course of track of the hoisted load. And
then, the image processor analyses the position, swing angle, cable
parameters, and further generates a feedback signal to the crane
controller for operating the trolley, so as to correct the drive
signal issued from the crane controller. As such, the drive unit
adjusts a moving speed of the trolley according to the corrected
drive signal. By means of this feedback mechanism, the swing amount
of the hoisted load may be lowered to a minimum, and the detection
and load swing suppression issues may be addressed, so that the
safety issue of a operator in a operation space.
[0035] In view of the above, the control device for a overhead
crane system may determine if there is any load swing by employing
the image processing technology to overcome the issue encountered
in the prior art. Since the detection and load swing suppression
purposes are achieved, the hand-off operator may be protected with
his safety issue.
[0036] From all these views, the present invention may be deemed as
being more effective, practical, useful for the consumer's demand,
and thus may meet with the requirements for a patent.
[0037] The above described is merely examples and preferred
embodiments of the present invention, and not exemplified to intend
to limit the present invention. Any modifications and changes
without departing from the scope of the spirit of the present
invention are deemed as within the scope of the present invention.
The scope of the present invention is to be interpreted with the
scope as defined in the claims.
* * * * *